What is the primary purpose of Cloud Cost Optimisation strategies such as Reserved Instances, Spot Instances, and Right-sizing?

Cloud Cost Optimisation is the process of reducing cloud spending without compromising operational requirements. Key strategies include Reserved Instances (1 or 3-year commitments for predictable workloads — up to 75% savings), Spot/Preemptible Instances (use spare capacity at 60–90% discount for fault-tolerant batch workloads), Right-sizing (matching instance type to actual resource needs — avoiding over-provisioned instances), Auto Scaling (paying only for resources needed at any given time), Storage Tiering (moving infrequently accessed data to cheaper storage classes), and Deleting Idle Resources (unused instances, unattached volumes, orphaned snapshots). Cloud cost optimisation is a critical IT governance responsibility for publicly accountable institutions.